/*
* (C) 2010,2014,2015,2018 Jack Lloyd
* (C) 2017 René Korthaus, Rohde & Schwarz Cybersecurity
*
* Botan is released under the Simplified BSD License (see license.txt)
*/

#include "cli.h"

#if defined(BOTAN_HAS_X509_CERTIFICATES) && defined(BOTAN_TARGET_OS_HAS_FILESYSTEM)

#include <botan/certstor.h>
#include <botan/pk_keys.h>
#include <botan/pkcs8.h>
#include <botan/x509_ca.h>
#include <botan/x509cert.h>
#include <botan/x509path.h>
#include <botan/x509self.h>
#include <botan/data_src.h>
#include <botan/parsing.h>

#if defined(BOTAN_HAS_OCSP)
   #include <botan/ocsp.h>
#endif

namespace Botan_CLI {

class Sign_Cert final : public Command
   {
   public:
      Sign_Cert()
         : Command("sign_cert --ca-key-pass= --hash=SHA-256 "
                   "--duration=365 --emsa= ca_cert ca_key pkcs10_req") {}

      std::string group() const override
         {
         return "x509";
         }

      std::string description() const override
         {
         return "Create a CA-signed X.509 certificate from a PKCS #10 CSR";
         }

      void go() override
         {
         Botan::X509_Certificate ca_cert(get_arg("ca_cert"));
         std::unique_ptr<Botan::Private_Key> key;
         const std::string pass = get_arg("ca-key-pass");
         const std::string emsa = get_arg("emsa");
         const std::string hash = get_arg("hash");

         if(!pass.empty())
            {
            key.reset(Botan::PKCS8::load_key(get_arg("ca_key"), rng(), pass));
            }
         else
            {
            key.reset(Botan::PKCS8::load_key(get_arg("ca_key"), rng()));
            }

         if(!key)
            {
            throw CLI_Error("Failed to load key from " + get_arg("ca_key"));
            }

         std::map<std::string, std::string> options;
         if(emsa.empty() == false)
            options["padding"] = emsa;

         Botan::X509_CA ca(ca_cert, *key, options, hash, rng());

         Botan::PKCS10_Request req(get_arg("pkcs10_req"));

         auto now = std::chrono::system_clock::now();

         Botan::X509_Time start_time(now);

         typedef std::chrono::duration<int, std::ratio<86400>> days;

         Botan::X509_Time end_time(now + days(get_arg_sz("duration")));

         Botan::X509_Certificate new_cert = ca.sign_request(req, rng(), start_time, end_time);

         output() << new_cert.PEM_encode();
         }
   };

BOTAN_REGISTER_COMMAND("sign_cert", Sign_Cert);

class Cert_Info final : public Command
   {
   public:
      Cert_Info() : Command("cert_info --fingerprint file") {}

      std::string group() const override
         {
         return "x509";
         }

      std::string description() const override
         {
         return "Parse X.509 certificate and display data fields";
         }

      void go() override
         {
         const std::string arg_file = get_arg("file");

         std::vector<uint8_t> data = slurp_file(get_arg("file"));

         Botan::DataSource_Memory in(data);

         while(!in.end_of_data())
            {
            try
               {
               Botan::X509_Certificate cert(in);

               try
                  {
                  output() << cert.to_string() << std::endl;
                  }
               catch(Botan::Exception& e)
                  {
                  // to_string failed - report the exception and continue
                  output() << "X509_Certificate::to_string failed: " << e.what() << "\n";
                  }

               if(flag_set("fingerprint"))
                  output() << "Fingerprint: " << cert.fingerprint("SHA-256") << std::endl;
               }
            catch(Botan::Exception& e)
               {
               if(!in.end_of_data())
                  {
                  output() << "X509_Certificate parsing failed " << e.what() << "\n";
                  }
               }
            }
         }
   };

BOTAN_REGISTER_COMMAND("cert_info", Cert_Info);

#if defined(BOTAN_HAS_OCSP) && defined(BOTAN_HAS_HTTP_UTIL)

class OCSP_Check final : public Command
   {
   public:
      OCSP_Check() : Command("ocsp_check --timeout=3000 subject issuer") {}

      std::string group() const override
         {
         return "x509";
         }

      std::string description() const override
         {
         return "Verify an X.509 certificate against the issuers OCSP responder";
         }

      void go() override
         {
         Botan::X509_Certificate subject(get_arg("subject"));
         Botan::X509_Certificate issuer(get_arg("issuer"));
         std::chrono::milliseconds timeout(get_arg_sz("timeout"));

         Botan::Certificate_Store_In_Memory cas;
         cas.add_certificate(issuer);
         Botan::OCSP::Response resp = Botan::OCSP::online_check(issuer, subject, &cas, timeout);

         auto status = resp.status_for(issuer, subject, std::chrono::system_clock::now());

         if(status == Botan::Certificate_Status_Code::OCSP_RESPONSE_GOOD)
            {
            output() << "OCSP check OK\n";
            }
         else
            {
            output() << "OCSP check failed " << Botan::Path_Validation_Result::status_string(status) << "\n";
            }
         }
   };

BOTAN_REGISTER_COMMAND("ocsp_check", OCSP_Check);

#endif // OCSP && HTTP

class Cert_Verify final : public Command
   {
   public:
      Cert_Verify() : Command("cert_verify subject *ca_certs") {}

      std::string group() const override
         {
         return "x509";
         }

      std::string description() const override
         {
         return "Verify if the passed X.509 certificate passes path validation";
         }

      void go() override
         {
         Botan::X509_Certificate subject_cert(get_arg("subject"));
         Botan::Certificate_Store_In_Memory trusted;

         for(auto const& certfile : get_arg_list("ca_certs"))
            {
            trusted.add_certificate(Botan::X509_Certificate(certfile));
            }

         Botan::Path_Validation_Restrictions restrictions;

         Botan::Path_Validation_Result result =
            Botan::x509_path_validate(subject_cert,
                                      restrictions,
                                      trusted);

         if(result.successful_validation())
            {
            output() << "Certificate passes validation checks\n";
            }
         else
            {
            output() << "Certificate did not validate - " << result.result_string() << "\n";
            }
         }
   };

BOTAN_REGISTER_COMMAND("cert_verify", Cert_Verify);

class Gen_Self_Signed final : public Command
   {
   public:
      Gen_Self_Signed()
         : Command("gen_self_signed key CN --country= --dns= "
                   "--organization= --email= --days=365 --key-pass= --ca --hash=SHA-256 --emsa= --der") {}

      std::string group() const override
         {
         return "x509";
         }

      std::string description() const override
         {
         return "Generate a self signed X.509 certificate";
         }

      void go() override
         {
         std::unique_ptr<Botan::Private_Key> key(Botan::PKCS8::load_key(get_arg("key"), rng(), get_arg("key-pass")));

         if(!key)
            {
            throw CLI_Error("Failed to load key from " + get_arg("key"));
            }

         const size_t days = get_arg_sz("days");

         Botan::X509_Cert_Options opts("", days * 24 * 60 * 60);

         opts.common_name  = get_arg("CN");
         opts.country      = get_arg("country");
         opts.organization = get_arg("organization");
         opts.email        = get_arg("email");
         opts.more_dns = Botan::split_on(get_arg("dns"), ',');
         const bool der_format = flag_set("der");

         std::string emsa = get_arg("emsa");

         if(emsa.empty() == false)
            opts.set_padding_scheme(emsa);

         if(flag_set("ca"))
            {
            opts.CA_key();
            }

         Botan::X509_Certificate cert = Botan::X509::create_self_signed_cert(opts, *key, get_arg("hash"), rng());

         if(der_format)
            {
            auto der = cert.BER_encode();
            output().write(reinterpret_cast<const char*>(der.data()), der.size());
            }
         else
            output() << cert.PEM_encode();
         }
   };

BOTAN_REGISTER_COMMAND("gen_self_signed", Gen_Self_Signed);

class Generate_PKCS10 final : public Command
   {
   public:
      Generate_PKCS10()
         : Command("gen_pkcs10 key CN --country= --organization= "
                   "--email= --dns= --ext-ku= --key-pass= --hash=SHA-256 --emsa=") {}

      std::string group() const override
         {
         return "x509";
         }

      std::string description() const override
         {
         return "Generate a PKCS #10 certificate signing request (CSR)";
         }

      void go() override
         {
         std::unique_ptr<Botan::Private_Key> key(Botan::PKCS8::load_key(get_arg("key"), rng(), get_arg("key-pass")));

         if(!key)
            {
            throw CLI_Error("Failed to load key from " + get_arg("key"));
            }

         Botan::X509_Cert_Options opts;

         opts.common_name  = get_arg("CN");
         opts.country      = get_arg("country");
         opts.organization = get_arg("organization");
         opts.email        = get_arg("email");
         opts.more_dns     = Botan::split_on(get_arg("dns"), ',');

         for(std::string ext_ku : Botan::split_on(get_arg("ext-ku"), ','))
            {
            opts.add_ex_constraint(ext_ku);
            }

         std::string emsa = get_arg("emsa");

         if(emsa.empty() == false)
            opts.set_padding_scheme(emsa);

         Botan::PKCS10_Request req = Botan::X509::create_cert_req(opts, *key, get_arg("hash"), rng());

         output() << req.PEM_encode();
         }
   };

BOTAN_REGISTER_COMMAND("gen_pkcs10", Generate_PKCS10);

}

#endif